U.S. patent number 6,926,700 [Application Number 10/391,832] was granted by the patent office on 2005-08-09 for needle assembly.
This patent grant is currently assigned to Becton, Dickinson and Company, Becton, Dickinson and Company. Invention is credited to Peter W. Bressler, John Coleman, Mathieu Turpault.
United States Patent |
6,926,700 |
Bressler , et al. |
August 9, 2005 |
Needle assembly
Abstract
The present invention is directed to a shieldable blood
collection set and a needle assembly. The needle assembly includes
a needle cannula having a puncture tip at a distal end, and a
needle retraction mechanism including a hub portion at a proximal
end which supports the needle cannula, a shield portion at a distal
end, and an extendable member hingedly connected therebetween. The
hub portion includes a lateral hub extension extending toward a
distal end of the needle cannula, and the shield portion includes a
lateral shield extension extending toward a proximal end of said
needle cannula. Opposing lateral forces applied against the
extendable member and an opposing lateral side of the needle
retraction mechanism cause relative axial movement between the hub
portion and the shield portion between a first sampling state with
the puncture exposed, and a second shielded state with the puncture
tip contained within the shield portion.
Inventors: |
Bressler; Peter W.
(Philadelphia, PA), Coleman; John (Philadelphia, PA),
Turpault; Mathieu (Berwyn, PA) |
Assignee: |
Becton, Dickinson and Company
(Franklin Lakes, NJ)
|
Family
ID: |
28045525 |
Appl.
No.: |
10/391,832 |
Filed: |
March 19, 2003 |
Current U.S.
Class: |
604/263 |
Current CPC
Class: |
A61M
25/0625 (20130101); A61B 5/15003 (20130101); A61B
5/150389 (20130101); A61B 5/150503 (20130101); A61B
5/153 (20130101); A61B 5/150656 (20130101); A61B
5/15074 (20130101); A61M 5/3269 (20130101); A61M
2005/325 (20130101) |
Current International
Class: |
A61B
5/15 (20060101); A61M 25/06 (20060101); A61M
5/32 (20060101); A61M 005/00 () |
Field of
Search: |
;604/192,263,110,198,187,158 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Sirmons; Kevin C.
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application
No. 60/365,479 filed Mar. 19, 2002.
Claims
What is claimed is:
1. A needle assembly, comprising: a needle cannula having a
proximal end and a distal end with a puncture tip; a hub member
supporting the proximal end of the needle cannula, said hub member
having first and second lateral sides and including a lateral hub
extension extending along said first lateral side in an axial
direction toward said distal end of said needle cannula, said hub
member further including a hub leg hingedly extending from said
lateral hub extension; and a shield member including an internal
passageway extending therethrough for accommodating said needle
cannula, said shield member having first and second lateral sides
corresponding to said first and said second lateral sides of said
hub member, said shield member including a lateral shield extension
extending along said second lateral side thereof in an axial
direction toward said proximal end of said needle cannula, said
shield member further including a shield leg hingedly extending
therefrom at said first lateral side with said hub leg and said
shield leg hingedly connected to each other forming a single pair
of hinged legs, wherein said shield member includes a rail
extending in an axial direction substantially parallel with said
needle cannula, and said hub member includes a guide channel for
engagement with said rail, wherein said lateral hub extension and
said lateral shield extension are engageable with each other to
form a unitary structure; said hub member and said shield member
include interengaging structures for relative axial movement with
respect to each other between a first position in which said needle
assembly is in a sampling state with said puncture tip of said
needle cannula exposed from said shield member, and a second
position in which said needle assembly is in a shielded state with
said puncture tip of said needle cannula contained within said
shield member; and wherein opposing lateral forces applied against
said hinged connection between said hub leg and said shield leg and
against said lateral shield extension cause said relative axial
movement of said shield member and said hub member between said
first position and said second position, thereby shielding said
needle cannula.
2. A needle assembly as in claim 1, further comprising structure
for preventing relative axial movement of said hub member and said
shield member from said second position to said first position.
3. A needle assembly as in claim 2, wherein at least one of said
hub leg or said shield leg includes a latch mechanism for
engagement with at least one of said hub member or said shield
member, respectively, when said hub member and said shield member
are moved to said second position.
4. A shieldable blood collection set comprising: a fixture for
connecting the blood collection set to a receptacle; a needle
cannula having a proximal end and a distal end with a puncture tip;
a flexible tube having opposed first and second ends, said first
end of said flexible tube being connected to said fixture; a hub
interconnecting said proximal end of said needle cannula and said
second end of said flexible tube, said hub including a lateral hub
extension extending laterally in an axial direction toward said
distal end of said needle cannula, said hub further including a hub
leg hingedly extending from said lateral extension; and a shield
including an internal passageway for accommodating said needle
cannula, said shield including a lateral shield extension extending
laterally in an axial direction toward said proximal end of said
needle cannula at a location opposing said lateral hub extension,
said shield further including a shield leg hingedly extending
therefrom with said hub leg and said shield leg hingedly connected
to each other forming a single pair of hinged legs, wherein said
shield includes a rail extending in an axial direction
substantially parallel with said needle cannula toward said
proximal end of said needle cannula, and said hub includes a guide
channel for engagement with said rail, wherein said lateral hub
extension and said lateral shield extension are engageable with
each other to form a unitary structure; said hub and said shield
include interengaging structure for relative axial movement with
respect to each other between a first position in which said needle
assembly is in a sampling state with said puncture tip of said
needle cannula exposed from said shield, and a second position in
which said needle assembly is in a shielded state with said
puncture tip of said needle cannula contained within said shield;
and wherein opposing lateral forces applied against said hinged
connection between said hub leg and said shield leg and against
said lateral shield extension causes said relative axial movement
of said shield and said hub between said first position and said
second position, thereby shielding said needle cannula.
5. A blood collection set as in claim 4, further comprising
structure for preventing relative axial movement of said hub and
said shield from said second position to said first position.
6. A blood collection set as in claim 5, wherein at least one of
said hub leg or said shield leg includes a latch mechanism for
engagement with at least one of said hub or said shield,
respectively, when said hub and said shield are moved to said
second position.
7. A blood collection set as in claim 4, further comprising a tip
guard including a metallic spring clip mounted to said shield, said
spring clip being biased against said needle cannula when said hub
and said shield are in said sampling state and being resiliently
moved over said distal end of said needle cannula when said hub and
said shield are in said shielded state.
8. A blood collection set as in claim 4, further comprising a
needle cover.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to blood collection sets for safe and
convenient handling of needles. More particularly, the present
invention relates to a blood collection set including a needle
assembly having a needle cannula which is retractable within a
safety shield for protection from a used needle tip.
2. Description of Related Art
Disposable medical devices having medical needles are used for
administering medication or withdrawing fluid from the body of a
patient. Such disposable medical devices typically include blood
collecting needles, fluid handling needles, and assemblies thereof.
Current medical practice requires that fluid containers and needle
assemblies used in such devices be inexpensive and readily
disposable. Consequently, existing blood collection devices
typically employ some form of durable, reusable holder on which
detachable and disposable medical needles and fluid collection
tubes may be mounted. A blood collection device of this nature may
be assembled prior to use and then disassembled after use. Thus,
these blood collection devices allow repeated use of a relatively
expensive holder upon replacement of relatively inexpensive medical
needles and/or fluid collection tubes. In addition to reducing the
cost of collecting blood specimens, these blood collection devices
help minimize the production of hazardous waste material.
A blood collection device or intravenous (IV) infusion device
typically includes a needle cannula having a proximal end, a
pointed distal end, and a lumen extending therebetween. The
proximal end of the needle cannula is securely mounted in a plastic
hub defining a central passage that communicates with the lumen
extending through the needle cannula. A thin flexible thermoplastic
tube is connected to the hub and communicates with the lumen of the
needle cannula. The end of the plastic tube remote from the needle
cannula may include a fixture for connecting the needle cannula to
a blood collection tube or other receptacle. The specific
construction of the fixture will depend upon the characteristics of
the receptacle to which the fixture is to be connected.
In order to reduce the risk of incurring an accidental needle-stick
wound, protection of used needle cannulas becomes important. With
concern about infection and transmission of diseases, methods and
devices to enclose or cover the used needle cannula have become
very important and in great demand in the medical field. For
example, needle assemblies commonly employ a safety shield that can
be moved into shielding engagement with a used needle cannula to
minimize risk of an accidental needle stick.
For example, U.S. Pat. No. 5,120,320 to Fayngold discloses an
intravenous infusion set or a blood collection assembly with an
automatic safety feature incorporating a needle cannula and a
safety shield, in which the needle cannula can be pulled rearwardly
such that the shield can be extended over the puncture tip of the
needle. The assembly further includes flexible wings which can be
used as means for securing the needle assembly to the skin of a
patient during a medical procedure. Positioning of the shield over
the needle, however, requires the user to maintain the shield with
one hand while withdrawing the needle into the shield with the
other hand, thus resulting in a complex two-handed operation for
the medical practitioner.
U.S. Pat. No. 5,951,525 to Thorne et al. discloses a manually
operated safety needle apparatus that includes two pairs of opposed
legs adapted to move a shield of the apparatus to a position
covering the used needle cannula. Such an assembly requires a
complex arrangement with extensive mechanics for activation of the
shield over the needle cannula, which can result in increased costs
for manufacture and assembly. Additionally, activation of the
needle assembly to move the shield into the proper position over
the pointed distal end of the needle cannula requires movement of
both pairs of legs toward each other, which can be awkward for the
user.
In view of the foregoing, a need exists for a blood collection set
including a shieldable needle assembly that achieves secure and
effective shielding of a used needle cannula, which is simple and
inexpensive to manufacture and easy to operate, and which has an
improved ergonomic feel to the user.
SUMMARY OF THE INVENTION
The present invention is directed to a shieldable blood collection
set, as well as a needle assembly for use in a blood collection
set. The needle assembly includes a needle cannula having a
proximal end and a distal end with a puncture tip, and a needle
retraction mechanism having a hub portion at a proximal end thereof
and a shield portion at a distal end thereof. The needle cannula is
supported at its proximal end by the hub portion of the needle
retraction mechanism, and extends through an internal passageway
and out from an open end of the shield portion. The needle
retraction mechanism includes opposing first and second lateral
sides, with the hub portion including a lateral hub extension
extending along the first lateral side in an axial direction toward
the distal end of the needle cannula, and the shield portion
including a lateral shield extension extending along the second
lateral side in an axial direction toward the proximal end of the
needle cannula.
The hub portion and the shield portion are adapted for relative
axial movement with respect to each other between a first position
in which the needle assembly is in a sampling state with the
puncture tip of the needle cannula exposed from the open end of the
shield portion, and a second position in which the needle assembly
is in a shielded state with the puncture tip of the needle cannula
contained within the shield portion. The needle retraction
mechanism includes an extendable member hingedly connected between
the hub portion and the shield portion at one of the first or
second opposing lateral sides of the needle retraction mechanism
for causing such relative axial movement. For example, the
extendable member may include a pair of folding legs connected by a
hinged knee joint, with one leg of the extendable member hingedly
connected to the hub portion and the other leg of the extendable
member hingedly connected to the shield portion. Opposing lateral
forces applied against the extendable member and the opposing side
of the needle retraction mechanism cause relative axial movement of
the shield portion and the hub portion between the first position
and the second position, thereby shielding the needle cannula.
The needle retraction mechanism may be in the form of a generally
planar structure extending in a generally upright manner along the
needle assembly, to form a generally fin-shaped structure for
providing an ergonomic design for the user during insertion of the
needle assembly into a patient. Desirably, the needle retraction
mechanism includes a generally flat bottom surface.
The hub portion and the shield portion may include interengaging
structure for permitting axial movement of the hub portion and the
shield portion in opposing axial directions. For example, the
shield portion may include a rail extending in an axial direction
substantially parallel with the needle cannula, and the hub portion
may include a guide channel for engagement with such a rail.
The needle assembly may further include structure for preventing
relative axial movement of the hub portion and the shield portion
from the second position to the first position after the assembly
has been activated to the shielded state. For example, the
extendable member may include a latch mechanism for engagement with
the needle retraction mechanism when the hub portion and the shield
portion are moved to the second position. Also, the shield portion
may include a tip guard having a metallic spring clip mounted to
the needle retraction mechanism, with the spring clip being biased
against the needle cannula when the needle assembly is in the
sampling state and being resiliently moved over the distal end of
the needle cannula when the needle assembly is in the shielded
state.
In a further embodiment, the present invention is directed to a
needle assembly including a needle cannula having a proximal end
and a distal end with a puncture tip, a hub member supporting the
proximal end of the needle cannula, and a shield member including
an internal passageway extending therethrough for accommodating the
needle cannula. The hub member includes first and second lateral
sides, as well as a lateral hub extension extending along the first
lateral side in an axial direction toward the distal end of the
needle cannula. The shield member also includes first and second
lateral sides corresponding to the first and second lateral sides
of the hub member, as well as a lateral shield extension extending
along the second lateral side thereof in an axial direction toward
the proximal end of the needle cannula. Also, the hub member
further includes a hub leg hingedly extending from the lateral
extension, while the shield member further includes a shield leg
hingedly extending from the first lateral side thereof, with the
hub leg and the shield leg hingedly connected to each other. The
lateral hub extension and the lateral shield extension are
engageable with each other to form a unitary structure, and the hub
member and the shield member include interengaging structure for
relative axial movement with respect to each other. Opposing
lateral forces applied against the hinged connection between the
hub leg and the shield leg and against the lateral shield extension
cause relative axial movement of the shield member and the hub
member between a first position in which the needle assembly is in
a sampling state with the puncture tip of the needle cannula
exposed from the shield member, and a second position in which the
needle assembly is in a shielded state with the puncture tip of the
needle cannula contained within the shield member, thereby
retracting the needle and shielding the needle cannula.
In yet a further embodiment, the present invention is directed to a
shieldable blood collection set including a fixture for connecting
the blood collection set to a receptacle; a needle cannula having a
proximal end and a distal end with a puncture tip; a flexible tube
having a first end connected to the fixture and an opposed second
end; a hub interconnecting the proximal end of the needle cannula
and the second end of the flexible tube; and a shield including an
internal passageway for accommodating the needle cannula. The hub
and the shield include structure as defined in the needle assembly
above, with the hub including a lateral hub extension extending
laterally in an axial direction toward the distal end of the needle
cannula and further including a hub leg hingedly extending from the
lateral extension, and with the shield including a lateral shield
extension extending laterally in an axial direction toward the
proximal end of the needle cannula at a location opposing the
lateral extension of the hub, and with the shield further including
a shield leg hingedly extending therefrom, such that the hub leg
and the shield leg are hingedly connected to each other. The
lateral hub extension and the lateral shield extension are
engageable with each other to form a unitary structure. Moreover,
the hub and the shield include interengaging structure for relative
axial movement with respect to each other between a first position
in which the needle assembly is in the sampling state and a second
position in which the needle assembly is in a shielded state.
Opposing lateral forces applied against a hinged connection between
the hub leg and the shield leg and against the lateral extension of
the shield causes such relative axial movement, thereby retracting
the needle and shielding the needle cannula.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a blood collection set in
accordance with the present invention;
FIG. 2 is a perspective view of a needle assembly in accordance
with the present invention shown in a sampling state;
FIG. 3 is a perspective view of the needle assembly of FIG. 2 shown
in a partially shielded state;
FIG. 4 is a perspective view of the needle assembly of FIG. 2 shown
in a fully shielded state;
FIG. 5 is a reverse perspective view of the needle assembly of FIG.
4 shown in a fully shielded state;
FIG. 6 is a cross-sectional view taken along line VI--VI of FIG. 2
with the needle assembly in a sampling state;
FIG. 7 is a cross-sectional view taken along line VII--VII of FIG.
5 with the needle assembly in a fully shielded state;
FIG. 8 is a side cross-section of a needle assembly in a sampling
state in an alternate embodiment of the present invention including
a tip guard assembly; and
FIG. 9 is a side cross-section of a needle assembly in a shielded
state in an alternate embodiment of the present invention including
a tip guard assembly.
DETAILED DESCRIPTION
Referring to the drawings in which like reference characters refer
to like parts throughout the several views thereof, FIG. 1
illustrates a blood collection set 10 in accordance with the
present invention and the related features. The present invention
is generally described in terms of a blood collection set, and
encompasses such a blood collection set as well as a shieldable
needle assembly for use in such a blood collection set.
As shown in FIG. 1, blood collection set 10 includes a shieldable
needle assembly 12, a flexible tube 14 extending from needle
assembly 12 and a fixture 16 mounted to flexible tube 14.
Shieldable needle assembly 12 of blood collection set 10 is shown
in detail in FIGS. 2-7, and includes a needle cannula 20 and a
needle retraction mechanism 30. Fixture 16 is connectable to a
receptacle (not shown) for use in blood collection procedures, as
is known in the art.
The shieldable needle assembly 12 of blood collection set 10
includes a needle cannula 20. Needle cannula 20 has a proximal end
22 and an opposing distal end 24. Needle cannula 20 defines a lumen
26 extending through needle cannula 20 from proximal end 22 to
distal end 24. Distal end 24 of needle cannula 20 is beveled to
define a sharp puncture tip 28, such as an IV puncture tip.
Puncture tip 28 is provided for insertion into a patient's blood
vessel, such as a vein, and is, therefore, designed to provide ease
of insertion and minimal discomfort during venipuncture. A
removable protective needle cover 18 may be positioned over distal
end 24 of needle cannula 20 for protection from puncture tip 28
prior to use of blood collection set 10, as shown in FIG. 1.
The shieldable needle assembly 12 of the blood collection set 10
further includes a needle retraction mechanism 30. In general,
needle retraction mechanism 30 includes proximal end 32, distal end
34, first lateral side 36, and second lateral side 38. Proximal end
32 of needle retraction mechanism 30 defines a hub portion or hub
member 40, while distal end 34 of needle retraction mechanism 30
defines a shield portion or shield member 70. An extendable member
62 is interconnected between hub member 40 and shield member 70 at
first lateral side 36. Hub member 40, shield member 70, and
extendable member 62 are interengageable to form a unitary
structure. As such, they may be formed as a single structure with
hinged connections therebetween, for example through a molding
process, and may be constructed of any known material, such as a
thermoplastic material.
As shown in FIGS. 1 and 2, with hub member 40 and shield member 70
interengaged to form a unitary structure, needle retraction
mechanism 30 includes a generally planar structure which extends in
a generally upright manner along needle assembly 12. Such an
arrangement forms a generally fin-shaped structure, which provides
an ergonomic feel for ease of use.
The hub member 40 of needle retraction mechanism 30 is generally
defined by a housing 42, and includes proximal end 44 and distal
end 46, with internal passage 48 extending from proximal end 44 to
distal end 46. Hub member 40 further includes first lateral side 50
and second lateral side 52. Hub member 40 is adapted to support
proximal end 22 of needle cannula 20. In particular, needle cannula
20 is positioned within internal passage 48 of hub member 40 and
extends outward from distal end 46 of hub member 40. Preferably,
needle cannula 20 and hub member 40 are formed as separate parts
that are fixedly attached and secured through an appropriate
medical grade adhesive, by direct mechanical attachment, or other
similar means.
Hub member 40 further includes a lateral hub extension 54 extending
along first lateral side 50 of hub member 40 to define distal end
46 of hub member 40. In particular, lateral hub extension 54
extends axially along first lateral side 36 of needle retraction
mechanism 30 from hub member 40 in a direction toward distal end 34
of needle retraction mechanism 30 and distal end 24 of needle
cannula 20, with hub member 40 further including hub shoulder 56
defined by the juncture of lateral hub extension 54 extending from
hub member 40.
As described above, needle assembly 12 is provided for attachment
to flexible tube 14, for example, for use in blood collection set
10. Hub member 40 may include a hub nub 64 for providing means for
attachment of flexible tube 14 to needle assembly 12.
Needle retraction mechanism 30 of needle assembly 12 further
includes shield member 70. The shield member 70 is generally
defined by a housing 72, and includes proximal end 74 and distal
end 76, with internal passage 78 extending from proximal end 76 to
and through distal end 78 at distal opening 80. A portion of
housing 72 defined by needle enclosure 90 extends co-axially about
needle cannula 20, with internal passage 78 extending through
needle enclosure 90 and in axial alignment with internal passage 48
of hub member 40.
Shield member 70 further includes first lateral side 82 and second
lateral side 84. A lateral shield extension 86 extends along second
lateral side 84 of shield member 70 to define proximal end 74 of
shield member 70. In particular, lateral shield extension 86
extends axially along second lateral side 38 of needle retraction
mechanism 30 from shield member 70 in a direction toward proximal
end 32 of needle retraction mechanism 30 and proximal end 22 of
needle cannula 20. Shield member 70 further includes shield
shoulder 88 defined by the juncture of lateral shield extension 86
extending from shield member 70.
Lateral hub extension 54 and hub shoulder 56 of hub member 40 are
interengageable with lateral shield extension 86 and shield
shoulder 88 of shield member 70 to form a unitary structure for
needle retraction mechanism 30. In particular, the leading edge of
lateral hub extension 54, which forms distal end 46 of hub member
40, engages against the face of shield shoulder 88, while the
leading edge of lateral shield extension 86, which forms proximal
end 74 of shield member 70, engages against the face of hub
shoulder 56. In this manner, lateral hub extension 54 and lateral
shield extension 86 are adjacent each other at opposing lateral
sides, thereby forming first lateral side 36 and second lateral
side 38 of needle retraction mechanism 30. Such a unitary structure
provides needle retraction mechanism 30 in a first position as
shown in FIG. 2, in which needle assembly 12 is in a sampling
state, with puncture tip 28 of needle cannula 20 extending through
internal passage 78 and exposed from distal opening 80 of shield
member 70.
Shield member 70 and hub member 40 of needle retraction mechanism
30 are axially movable relative to each other in opposing axial
directions, from this first position to a second position. In the
second position, the shield member 70 and the hub member 40 are
spaced from each other, with distal end 24 of needle cannula 20
contained within internal passage 78 of needle enclosure 90 of
shield member 70, such that puncture tip 28 of needle cannula 20
does not extend beyond distal opening 80 of shield member 70 but is
also contained within shield member 70. As such, when needle
retraction mechanism 30 is in the first position, as shown in FIG.
2, the needle assembly 12 is in a sampling state, capable of
venipuncture, as will be described in further detail. When needle
retraction mechanism 30 is extended from the first position to the
second position, as shown in FIGS. 3 and 4, needle cannula 20 is
retracted within shield member 70 and the needle assembly 12 moves
to a shielded state to protect the used puncture tip 28.
As noted, needle retraction mechanism 30 includes extendable member
62 extending from first lateral side 36 thereof. Hub member 40
includes hub leg 58 extending laterally from first lateral side 50
at lateral hub extension 54. Hub leg 58 is hingedly connected to
lateral hub extension 54 through hinged connection 60. Moreover,
shield member 70 includes shield leg 92 extending laterally from
first lateral side 82. Shield leg 92 is hingedly connected to
shield member 70 through hinged connection 94. Hub leg 58 and
shield leg 92 extend toward each other at first lateral side 36 of
needle retraction mechanism 30 to meet at hinged interconnection 96
forming a hinged knee joint. As such, the combination of hub leg 58
and shield leg 92 through the hinged connections 60 and 94, as well
as hinged interconnection 96, form extendable member 62 of needle
retraction mechanism 30. Extendable member 62 provides a mechanism
for causing activation of needle retraction mechanism 30 through
relative axial movement of hub member 40 and shield member 70 in
opposing axial directions, as will be discussed in more detail
herein.
Moreover, needle retraction mechanism 30 may include means for
frictional engagement with a user's fingers in order to assist in
activation to the shielded state. For example, shield leg 92 may
include one or more protrusions such as shield leg ribs 98 on an
outer surface thereof, and lateral shield extension 86 may
similarly include a set of extension ribs 100 on second lateral
side 84 of shield member 70. Such shield leg ribs 98 and extension
ribs 100 provide means for frictional engagement with a user's
fingers on opposing lateral sides of needle retraction mechanism
30.
Hub portion 40 and shield portion 70 of needle retraction mechanism
30 may further include interengaging structure for permitting
relative axial movement with respect to each other. For example, as
seen in FIGS. 5-7, shield member 70 may include guide rail 110
extending from shield member 70 in a direction toward the distal
end 34 of needle retraction mechanism 30. Such a guide rail 110 may
extend from shield shoulder 88 and may be attached to the inner
surface of lateral shield extension 86. Desirably, guide rail 110
may be integrally formed with shield member 70. Guide rail 110 may
further include extension lips 112 and 114 extending in opposing
directions from guide rail 110. Clasps 116 and 118 are provided on
hub member 40 for engagement with extension lips 112 and 114.
Clasps 116 and 118 may be integrally formed with hub member 40, and
desirably extend from the inner surface of lateral hub extension 54
toward second lateral side 52 of hub member 40, establishing a hub
channel 66 for accommodating guide rail 110. Clasps 116 and 118 are
designed to interengage extension lips 112 and 114 of guide rail
110, to permit axial movement therealong, and to prevent
disengagement therebetween. Also, guide rail 110 may include a stop
means at the end thereof, for preventing clasps 116 and 118 from
traveling axially beyond the end of guide rail 110 and becoming
disengaged therefrom.
Additionally, needle retraction mechanism 30 may include means for
preventing relative axial movement of hub member 40 and shield
member 70 from the second position to the first position once
needle assembly 12 has been activated from the sampling state to
the shielded state, thereby preventing a re-exposure of needle
cannula 20 and puncture tip 28. For example, as seen in FIGS. 2-4,
extendable member 62 may include a latch mechanism extending from
hub leg 58 or shield leg 92, such as a latch 102, for engagement
with a portion of needle retraction mechanism 30 when hub member 40
and shield member 70 are moved axially away from each other to the
second position when needle assembly 12 is moved into the fully
shielded state. Latch 102 includes latch lip 104, which extends
from latch 102. Latch lip 104 is provided for frictional engagement
with opening 106, which extends through shield member 70, such as
through the top portion of needle enclosure 90 of shield member 70.
Extendable member 62 is designed such that, when needle retraction
mechanism 30 is activated, hub leg 58 and shield leg 92 extend
toward a co-linear position substantially parallel with needle
cannula 20, thereby causing hub member 40 and shield member 70 to
move in opposing axial directions. In such a co-linear position,
latch 102 extending from shield leg 92 is moved to a position
adjacent shield member 70, and latch lip 104 engages with opening
106. As such, extendable member 62 is locked in place, thereby
locking needle assembly 12 in the shielded state.
Alternatively or in addition to such a latch, needle assembly 12
may further include a tip guard, such as tip guard assembly 120,
for providing a locking mechanism for preventing re-exposure of
puncture tip 28 through distal opening 80 of shield member 70, as
seen in FIGS. 8 and 9. Tip guard assembly 120 is desirably provided
within a portion of shield member 70 adjacent distal end 76 thereof
at internal clip receptacle 122. Tip guard assembly 120 includes a
protective clip 124. A clip mounting post 126 extends downwardly
from housing 72 of shield member 70, with clip 124 attached to
housing 72 through clip mounting post 126. Clip 124 is unitarily
stamped and formed from a resiliently deflectable metallic
material. Clip 124 includes a planar spring leg 128 with a proximal
end 130 and an opposed distal end 132. A lockout leg 134 extends
angularly from distal end 132 of spring leg 128. Lockout leg 134 is
bent back toward proximal end 130 of clip 124. The bends in lockout
leg 134 enable secure protective engagement with puncture tip 28 of
needle cannula 20 and further enable smooth axial sliding movement
of tip guard assembly 120 along needle cannula 20, as described in
further detail herein.
In an alternate embodiment, needle retraction mechanism 30 may
further be provided with means for passively causing relative axial
movement between hub member 40 and shield member 70 in opposing
axial directions. For example, a compression spring (not shown) may
be provided between hub member 40 and shield member 70, at a
position such as at guide rail 110 or extending axially about
needle cannula 20, between hub portion 40 and shield portion 70.
Such a compression spring may be in a compressed state when needle
retraction mechanism 30 is in the first position with hub member 40
and shield member 70 interfitting together. In such a compressed
state, the compression spring stores energy for moving hub member
40 and shield member 70 axially apart. In such an embodiment,
needle retraction mechanism 30 may include means for maintaining
hub member 40 and shield member 70 in this interfitting engagement,
thereby maintaining the compression spring in a compressed state.
When released, the energy stored in the compression spring is
released, thereby moving hub member 40 and shield member 70 in
opposing axial directions, causing needle assembly 12 to be moved
from the sampling state to the shielded state.
The overall profile and design of needle assembly 12 provides an
ergonomic feel to the user. In particular, needle retraction
mechanism 30 may include rounded lateral sides as best seen in
FIGS. 6 and 7, and a flat bottom surface. Such a configuration
provides for improved handling and operation during use.
With the basic structure of the blood collection set 10 and needle
assembly 12 described, operation of the blood collection set 10 and
needle assembly 12 will be described. In use, blood collection set
10 is provided with needle assembly 12 assembled as described and
including flexible tube 14 extending from needle assembly 12 and
connected to fixture 16. After removing blood collection set 10
from its package, it can be assembled with other appropriate
medical equipment for use. For example, an appropriate receptacle,
such as a non-patient needle assembly and a needle holder, may be
connected to blood collection set 10 through fixture 16, thereby
providing fluid communication with lumen 26 through needle cannula
20.
The needle assembly 12 is packaged in the sampling state, with
needle cover 18 positioned over the distal end 24 of the needle
cannula 20. To prepare for use of blood collection set 10, the user
grasps blood collection set 10 at needle assembly 12 and removes
the needle cover 18 to expose puncture tip 28 of needle cannula
20.
The medical practitioner then sterilizes the intended area of
puncture on the patient's body, and can then urge puncture tip 28
at distal end 24 of needle cannula 20 into a targeted blood vessel
of a patient. To insert the needle cannula 20, the user grasps
needle assembly 12 on opposing first and second lateral sides 36
and 38 of needle retraction mechanism 30. The generally planar
structure of needle retraction mechanism 30 extending in an upright
manner forming a fin-shaped structure provides an ergonomic design
for the user to assist in positioning the needle assembly 12 at the
intended area of puncture on the patient's body. Once the puncture
tip 28 of the needle cannula 20 is inserted into a blood vessel in
the patient's body (i.e., venipuncture), the user may secure needle
assembly 12 to the patient's body to maintain the positioning and
placement of the needle assembly 12 during the medical procedure,
for example, by taping retraction mechanism 62 in place with the
flat bottom surface of needle retraction mechanism 30 lying flat
against the patient's skin, or alternatively by rotating needle
assembly 12, such that second lateral side 38 lies flat against the
patient's skin and taping needle retraction mechanism 30 across
first lateral side 36 of needle retraction mechanism.
After completing the appropriate medical procedure such as infusion
or blood collection, the user of the blood collection set 10 and
needle assembly 12 can activate needle assembly 12 to shield the
puncture tip 28 with shield member 70. Activation can be
accomplished while venipuncture is maintained, or after needle
assembly 12 is removed from the patient. To activate needle
assembly 12, the user grasps needle retraction member 30 between a
finger and thumb at hinged interconnection 96 of extendable member
62 and at first lateral side 82 of shield member 70. Shield leg
ribs 98 and extension ribs 100 provide a raised tactile surface for
assisting the user in grasping of the needle retraction mechanism
30. The user then squeezes together against hinged interconnection
96 and first lateral side 82 in a direction toward the central axis
of needle assembly 12 and toward needle cannula 20. Such squeezing
forces extendable member 62 in a direction of arrow 140, through
pivoting of hub leg 58 at hinged connection 60 and shield leg 92 at
hinged connection 94, as well as pivoting of hub leg 58 and shield
leg 92 with respect to each other at hinged interconnection 96.
Such pivoting in turn forces hub member 40 and shield member 70 to
move in opposing axial directions with respect to each other in a
direction of arrows 142 and 144, respectively, from the first
position as shown in FIG. 2, through the position of FIG. 3, and to
the second position as shown in FIG. 4. The interengagement between
clasps 116 and 118 of hub member 40 and guide rail 110 of shield
member 70 permits such relative opposing axial movement of hub
member 40 and shield member 70, and maintains the general upright
orientation of hub member 40 and shield member 70 with respect to
each other. Since proximal end 22 of needle cannula 20 is connected
to hub member 40, such movement causes needle cannula 20 to axially
move within internal passage 78 of shield member 70 in a direction
of an arrow 146, and to retract within needle receptacle 90 of
shield member 70. Continued squeezing force applied against
extendable member 62 and second lateral side 84 causes distal end
24 and puncture tip 28 of needle cannula 20 to retract into distal
opening 80 of shield member 70 and into needle receptacle 90, and
causes shield leg 92 and hub leg 58 to extend to a generally
co-linear position, thereby placing latch 102 at a position
adjacent opening 106 of shield member 70. At such point, latch lip
104 can engage within opening 106, which provides a tactile feel to
the user that hub member 40 and shield member 70 have moved to the
second position, and effectively locks needle assembly 12 in the
shielded position.
Moreover, in embodiments incorporating a tip guard assembly 120,
clip 124 will automatically cover puncture tip 28 of needle cannula
20 once needle assembly 12 has been moved to the shielded state. In
particular, as shown in FIGS. 8 and 9, when hub member 40 and
shield member 70 are in the first position, needle cannula 20
extends outward from the housing 72 of the shield member 70 through
distal opening 80. Opposing axial movement of hub member 40 and
shield member 70 from the first position to the second position
causes clip 124 to move along needle cannula 20 to the distal end
24. At this point, lockout leg 134 of clip 124 will pass distally
beyond puncture tip 28 of needle cannula 20. The inherent
resiliency of spring leg 128 of clip 124 will urge lockout leg 134
over puncture tip 28 of needle cannula 20. Thus, re-exposure of
puncture tip 28 is prevented.
Furthermore, extendable member 62 has an overall dimension that
will prevent movement of shield member 70 distally beyond needle
cannula 20, and guide rail 110 may include stop means for
preventing hub member 40 from moving beyond guide rail 110. Hence,
puncture tip 28 of needle cannula 20 is safely shielded. Blood
collection set 10 may then be appropriately discarded.
It is noted that while activation of the safety feature may require
opposing squeezing forces applied against second lateral side 84
and against extendable member 62, as described above, needle
retraction mechanism 30 may also including a passive activation
feature, such as the compression spring described above. As such,
passive shielding of needle assembly 12 can be achieved upon
disengaging hub member 40 and shield member 70 from interfitting
engagement, thereby providing needle assembly 12 as an
automatically shieldable needle assembly.
While the needle assembly of the present invention has been
described in terms of one embodiment for use in connection with a
blood collection set, it is further contemplated that the needle
assembly could be used with other medical procedures, such as in
conjunction with a conventional IV infusion set, which are well
known in the art for use with needle assemblies.
While the present invention is satisfied by embodiments in many
different forms, there is shown in the Figures and described herein
in detail, the preferred embodiments of the invention, with the
understanding that the present disclosure is to be considered as
exemplary of the principles of the invention and is not intended to
limit the invention to the embodiments illustrated. Various other
embodiments will be apparent to and readily made by those skilled
in the art without departing from the scope and spirit of the
invention. The scope of the invention will be measured by the
appended claims and their equivalents.
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